Simulation Based Design Study of the Smart Cart

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Simulation Based Design Study of the Smart Cart

• ME 6105 Modeling Simulation
• Dr. Chris Paredis
• Harjot Hayer
• Daniel Lai
• Laura Raibeck

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What is the Smart Cart?

• Motivation
• Harjots Senior Design Project
• Brief Description
• Modeled after a Hydraulic Scissor Lift
• Main Objective was to Lift 150 lbs, and to Load
  onto a Vehicle
  through a 4-Step Process

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Smart Cart Video
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Project Overview

• Goals of the Design Study
• Maximize Usability
• Minimize Energy Consumption
• Maximize Performance
• Design Variables for Study
• Size of hydraulic cylinder
• Input Voltage
• Hydraulic configuration
• Measures of Effectiveness
• Time to reach height of 1m
• Energy Consumption (W)

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Dymola Models
Scissor Lift Models (1)
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Dymola Models Cont.
Scissor Lift Models (2)
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Dymola Models Cont.
Hydraulic Model
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Dymola Models Cont.
Complete Model
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Interesting Results
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• Uncertain Variables were Analyzed in ModelCenter

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BAD
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Problems Encountered

• Original Design Study
• Geometry as a Design Variable
• Goals Related to Payload
• Scope of study too large
• Planar Loops/Singularities!
• Knowledge of Hydraulics
• Changing one variable in many places
• Geometries for all links
• Friction in joints

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What We Learned

• How to Use Dymola Steep Learning Curve
• Organized models are easier to use
• ModelCenter
• Modeling preferences is difficult
• Dealing with uncertainty
• Dont leave hydraulics for last